Abstract : Experiments were performed involving condensation of supersaturated benzene and chloroform vapors in a supersonic nozzle, with compressed air as the carrier gas. Experiments showed that the magnitude of the water vapor content of the carrier air made no observable difference in the condensation behavior of either fluid. It was demonstrated that addition of small amounts of these fluids to the carrier air tended to reduce the thickness of the boundary layer in the nozzle. Comparison of experimental results with theory show, without making any adjustments to physical properties of condensate droplets to account for size, that incidence of condensation for chloroform can be predicted by the revised theory of nucleation, whereas benzene incidence can be predicted by neither revised nor classical theory. These results, combined with prior data on other fluids, show that at present neither theory seems to be generally applicable. In support of previous conclusions, the problem may well be the assumption that bulk properties may be assigned to small (30 - 50 molecules) droplets of condensate. (Author)